Up to 30,000 nurses and midwives nationwide are expected to strike, although many others would continue to work to ensure life-preserving services continued.
Non-essential services at Northland hospitals, including surgeries and appointments, have already been cancelled in anticipation of the strike.
In-hospital services will be delivered by other clinical and non-clinical staff, including NZNO nurses providing life-preserving services, as well as nurses, midwives, and healthcare assistants who are not on strike.
All Northland District Health Board services would be reduced during the strike, but the Emergency Department would remain open. People with less serious problems were advised to go to their GP or White Cross.
Director of nursing and midwifery Margareth Broodkoorn said a good number of volunteers had come forward to help during the strike.
''Our call for volunteer support was well received with both DHB staff, who normally work in other functions, and staff from other health providers answering the call and offering their skills and time over the strike period.
"We have also had a great response from members of the public, and at this point we have enough volunteers, so thanks to all of you who have offered."
The health board had comprehensive contingency management plans in place to ensure acute care and emergency services remained available, but patients would feel some effects from the strike.
''While the majority of our services are unaffected, this strike action will have an impact on patient care,'' Broodkoorn said.
Families and friends could play a part by sitting with patients and doing some care tasks. Nurses and other assistance would be on hand to help move patients and carry out other tasks untrained people were not confident doing.
Volunteer staff working over the 24-hour strike period would wear coloured vests to identify them.
NDHB's contingency planning continued even as nurses' votes were being cast up until Tuesday mid-morning in the online ballot.
Further talks between the health boards and NZNO would take place today, ordered by the Employment Relations Authority (ERA) in an attempt to find an eleventh hour resolution.
Yesterday NZNO refused to continue talks with the boards, saying there was no point if there were no funds for an improved offer, as the nurses had been told.
The ERA ruling over-rode the nurses' stance, but today while the talks will go ahead, tomorrow's strike action is still alive.
NZNO members previously voted to reject the DHBs' earlier offer of 9 per cent for all member nurses by August 2019, which equated to $500 million.
The latest vote was based on whether or not to strike. Turnout was high and the result closer than last time, NZNO industrial services manager Cee Payne said.
The strike decision described as ''unprecedented'' came after a decade of severe underfunding and a health service administration which has not kept pace with community needs and changes brought about by an ageing population and other effects, the nurses said.
